Essigella californica (Essig) and Eulachnus thunbergii Wilson (Hemiptera: Aphididae: Lachninae) on Pinus in south‐eastern Australia

Abstract

Accounts are given of two related, exotic lachnine aphid species colonising Pinus species in eastern Australia. Essigella californica (Essig), a recent adventive, is now abundant and widespread on Pinus radiata in south‐eastern Australia; its economic importance is discussed. Eulachnus thunbergii Wilson is commonly to be found on other, less extensively planted, species of Pinus in north‐eastern New South Wales. Means of distinguishing between the two species are provided.

Quantifying stem growth loss at the tree-level in a Pinus radiata plantation to repeated attack by the aphid, Essigella californica

“…There have been no equivalent studies for the P. radiata-E. californica interaction. Moisture stress however, has been implicated in the susceptibility of trees to aphid attack (Carver and Kent, 2000;Wharton and Kriticos, 2004). Moreover, in one of the very few studies that have examined the impact of repeated E. californica-induced defoliation on radial growth of >15-year-old P. radiata trees, the data was collected from three sites noted as experiencing moisture stress during the course of the eight-year study (Hopmans et al, 2008).…”

“…One of the more recent challenges for the profitable production of P. radiata plantations in Australia has been repeated defoliation by the exotic pest insect, Essigella californica Essig (Hemiptera: Aphididae) (May and Carlyle, 2003;May, 2004;Hopmans et al, 2008). First detected in 1998 (Carver and Kent, 2000), outbreaks of E. californica aphid have been closely associated with widespread needle yellowing and defoliation (up to 50%) of mid-rotation P. radiata plantations (e.g. Hopmans et al, 2008).…”

“…Represented by two morphs the winged alate form and the wingless aptera, E. californica feed singly on needle sap obtained through narrow stylet mouthparts . E. californica prefer to feed on one-year-old and older needles following a 'top-out' pattern of defoliation (Carver and Kent, 2000). That is, defoliation starts from mid-whorl and progresses to shoot tips then as severity increases, progresses up the terminal shoot and down into the lower crown, resulting in very thin mid to upper crowns.…”

Survey of damaging pests and preliminary assessment of forest health risks to the long term success of Pinus radiata introduction in Sichuan, southwest China

“…Sirex noctilio is endemic to regions to the north of China including Siberia and Mongolia (Spradbery and Kirk 1978), and research using climate matching has predicted it to be able to establish in China (Carnegie et al 2006). The arrival of California pine aphid, Essigella california Essig in Australia in 1998 and its apparent rapid dispersal across the country since then have been causing significant concern (Carver and Kent 2000). Between 1998 and 2001, its infestation in the Green Triangle region in the south-east South Australia and south-west Victoria caused an estimated growth reduction of 230,000 m 3 , valued at $6.9 million, in the mid-rotation P. radiata plantations (May and Carlyle 2003).…”

Forest health surveillance in South Australia

“…The Monterey pine aphid, Essigella californica (Essig), was first detected in Australia in 1998 (Carver and Kent 2000). Subsequent surveys across Australia revealed it to be widespread throughout plantations in several states, where it caused considerable defoliation and growth loss.…”